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2,330 Articles
9,158 Members
146 Directory Listings
155,251 Followers

The world's best gem articles, published weekly.

Most Recent Articles

Diamond Polish and Symmetry Explained

If you’re a first-time buyer, you may be worried about diamond polish and symmetry grades. But what do these grades mean, and do they impact price?

Table of Refractive Indices and Double Refraction of Selected Gems

Refractive indices and double refraction (birefringence) help gemologists identify gems. The following table lists these values for selected gemstones.

Sugilite Value, Price, and Jewelry Information

What is the color of sugilite? Grape jelly purple is a good description. More popular among consumers in Asia than North America, this is a very rare and beautiful opaque gem material with an unusual appearance.

Pear-Shaped Diamond Guide: Unique & Stylish

Dreaming of a pear-shaped diamond engagement ring? Learn the pros and cons and read our expert advice to find the perfect pear for your style and budget!

Is a D Color Flawless Diamond Worth the Price?

A D color flawless diamond has the highest color and clarity grade — and the biggest price tag. Are these premium diamonds worth the extra money?

Rose Quartz Value, Price, and Jewelry Information

A popular variety of colored quartz, rose quartz makes a durable jewelry stone. Although commonly cabbed and carved, more transparent material can also be faceted.

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"Becoming a Pro Member of IGS just made good sense for my business. The gemology resources are fantastic, and my profile lets potential customers know I am serious about colored gemstones. And frankly, if I get any exposure to potential customers it's a no-brainer."
Paul Bierker, Paul Michael Designs
Jeweler, IGS Pro Member

The world's best online resource for gemstone appraisal

Over 15 years, we have assembled detailed pricing and value information for appraising over 70 different gemstones. The values in our guide come from a variety of sources including primary and secondary gemstone dealers, jewelers, miners, and wholesale suppliers of commonly traded gemstones.

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